Presumption
by PyramidCalyx
Summary: Uncertain about their relationship, Brian decides to leave. Can Olivia stop him? One-shot, rated M.


A/N Hope you guys like this one. Thanks for reading!

**Presumption**

A streetlight flickered, its interrupted beam casting trembling shadows on the pavement. A faint breeze teased the edges of the drawn curtains. Brian Cassidy flicked the bedroom light on, sighing heavily. He threw a duffel bag onto the bed and rubbed his temple.

"I say we break-in every horizontal surface," her grin was akin to a Cheshire cat's. "You know, christen our new home."

Brian grinned, holding her hips in a tight grasp. "Yeah?"

With a broad smile, Olivia Benson turned in his arms, pushing her back against his solid frame. She pulled her t-shirt off in one swift motion and took a step out of Brian's embrace.

"Yeah," she purred, slowly undoing her jeans and wiggling them down her slender legs.

Brian growled, making her giggle. He reached for her but she spun around. "You've gotta catch me first!"

With that, she escaped from the bedroom. _God woman, you'll be the death of me_, Brian thought, quickly undoing his belt and tugging his t-shirt off. He dropped his pants and boxers, then wandered into the larger living space of their apartment. Olivia sat on the kitchen island, innocently swinging her legs.

"You wanna start here?" he put a hand on the top of each of her thighs and caressed her smooth skin.

"Mmhmm," she wrapped her hands around his neck, twisting her fingers in his hair. "In case you are hungry…"

Brian chuckled, pulling her to the edge of the counter. His lips met hers as she reached behind to undo her bra. He pulled the garment down her arms without breaking their kiss. Her mouth was warm and inviting, and he licked her bottom lip. She moaned and welcomed his tongue.

"Well, I do have a hankering for something," he murmured against her lips.

She gave him a sly grin and pulled him closer to her body, tightening her legs on either side of his hips. "And what might that be?" she whispered, moving her lips to his neck.

Brian slid his hands gently down her sides, hooking his fingers under the edge of her lace thong. She lifted herself as he slipped her last remaining piece of clothing off of her body. He then grabbed her face, attacking her lips. Olivia moaned, feeling the dampness increasing between her legs. She tugged Brian's hair as his mouth descended, weaving across her breasts and down to her navel.

"You," he responded, crouching so his mouth met her shaved mound. He pushed her legs apart as wide as she could stretch, and placed lingering kisses along the inside of her thighs.

"Bri," she murmured, her voice higher pitched than normal.

He licked up her slick slit, caressing her clit with his tongue, loving the sounds she was making. Her hands gripped his shoulders, her head thrown back in pure ecstasy. He gripped her legs tighter and continued his assault on her hot core, thrusting his tongue into her tight entrance. Olivia cried out, her fingernails piercing Brian's skin.

"Oh yes! Like that, baby," she yelled, her eyes unable to stay focussed.

His erection was painfully hard. He moaned against her soft, wet skin, bringing his mouth back to her clit. His tongue ran circles around the precious nub, and Olivia's moaning intensified. She was close. He wanted to make her come hard; then pound his aching cock into her tight pussy.

"Come, baby," he growled, before sucking her clit into his mouth. The mixture of his tongue swiping her bundle of nerves and dipping into her dripping centre pushed Olivia into a powerful orgasm. She cried his name as she came, feeling his tongue still thrusting inside of her.

"Fuck!" she exclaimed as he stood up and pulled her off of the counter, spinning her around. She arched her back and leaned forward, feeling him thrust his thick cock into her. "Brian!"

"Fuck, Liv, so tight, baby," he groaned, pushing in as deep as he could go.

Olivia loved the euphoria from feeling totally filled when Brian fucked her from behind. His hard dick pulled out before crashing back into her. She yelped and gripped the counter with white knuckles as he pummelled into her pussy. Both of them moaned with ragged breaths as his balls slapped her ass.

"Bri - Bri, come in me, baby," she murmured, pushing her hips back against his, meeting every thrust.

Brian squeezed her hips so tight he was sure there would be bruises in the morning. She didn't seem to mind, and turned her head to gaze over her shoulder at him. She made eye contact and licked her lips. Her eyes were black with lust, and his body erupted in pure pleasure. His load exploded inside of her, the gush of hot fluid making her shudder in utter bliss. He leaned against her, pulling her to standing position. She wrapped her arms around his arms, and they stood waiting for their breathing to even out. When he pulled out of her, she turned and hugged him tightly. He caressed her lower back and grazed her ass with his fingertips making her shiver.

"Mmm, I love you, Bri," she said, kissing him passionately.

Brian grinned, never tiring of hearing her say that. "Love you, too, baby," he kissed her slowly, deeply, running one hand up and into her hair. She smiled against his lips and caressed his cheek. 

A siren pierced his reverie. Brian ran a hand through his hair and opened the closet, tossing clothing haphazardly onto the bed. He rifled through his drawers, grabbing handfuls of socks and underwear. As he returned to the bed, he heard the front door open. He didn't turn around. Instead, he shoved clothing into the duffel bag, his shoulders sadly slumped in defeat.

"Bri?" Olivia's voice was soft, and she was trying her best not to let the sound of her voice belie the fear that spread throughout her heart.

"Yeah, Liv?" he replied, his back to her.

She took a tentative step inside the room. "What are you doing, Brian?"

He stopped and sighed. Part of him had wanted to finish this before she arrived home. _Coward_, he thought, ashamed of himself. "What does it look like?"

Olivia inhaled sharply, her lower lip starting to tremble. _No, this isn't happening,_ she thought. She closed her eyes tight, warding away the tears that threatened to fall. _This can't be the end. I can't lose him_.

"Can't we just - can't we talk, Brian?" she managed to get out as her heart pounded.

Brian clenched his jaw and turned to face her. "Talk? Talk about what, Olivia? About how we have the same argument, over and over again? About how we pretend everything is fine when we both know that's crap?" His anger made her tense. He had never yelled, nor looked at her with such hollow eyes.

"No? You aren't gonna talk about that because you _never_ talk about anything with me. Everything's always fine. I've been patient, I've been respectful of what _you're_ used to. But, I'm done, Olivia," he turned back to packing. "Nothing with you ever changes. Nothing ever will."

Olivia's eyes burned and her body jumped into panic mode. She could feel bile rising in her throat and the room started to sway. She reached for his arm and he shrugged her off. Everything in her world seemed to disappear into an abyss, and she couldn't find the light. She stood, frozen, watching the one man she truly loved rummage through their shared closet, yanking shirts off of hangers. She couldn't breathe. She couldn't compute what was happening.

"Bri-" she rasped, trying to touch him once more.

"No, Liv. I'm done being a bystander in your life. What I thought was gonna be _our_ life," he pushed past her into the en suite, collecting an armful of toiletries.

"I don't understand," she whispered, brushing the tears from her face. Moving in together had been an adjustment, yes, but she thought that phase had finished. They had fallen into sync with each other's habits and schedules. He had been given his shield back and returned to a regular detective's schedule with Homicide. They saw more of each other now that he wasn't working night shifts at the Bronx courthouse. She had diligently been balancing therapy sessions and work in such a way that they had time to spend together on free evenings and weekends. She didn't understand why he was leaving, or what she had done.

Brian zipped the duffel bag and double-checked the closet before leaving the room. Olivia followed him, her mind in a daze, heart shattered. He grabbed his coat out of the front closet and began pulling on his sneakers.

"What are you talking about?" she asked, silently cursing her voice for wavering. She never showed this much vulnerability in an argument; this time was different. "Brian, look at me!"

He looked up, his eyes wet with emotion. Olivia's chin trembled again, anxiety rising within her chest like an icy poison. She had never seen him cry. His eyes shone under the light, and she watched him swallow hard before speaking.

"You don't trust me, Liv, you don't," he said, hushed. She opened her mouth to object, but he shook his head. "I don't care what you say, you don't trust me enough to let me in here," he tapped his heart. "You tell yourself that you do, but I can see it in your eyes. You're still holding yourself back. And it's not just from your attack, this goes back before that."

Brian leaned heavily against the wall. He watched her trying to come up with a reply. He loved her more than anything in the world, but he couldn't bear to continue tricking her into thinking he was what she truly wanted. She had always been an enigma; like a bright star in the night that cloaks itself when you look directly at it. He had never felt so much passion and frenzy in his life since reuniting with her a year and a half prior. She was strong, stubborn, and so beautiful. The past few weeks he began to doubt his importance in her life. She hadn't physically distanced herself, but emotionally she had herself barricaded. He couldn't blame her; she had admitted to never having been adept at handling romantic relationships, and definitely had never taken the jump of cohabitation. But he knew he wanted more, and the more that he sought would likely terrify her. Olivia, with her edgy distrust of men and desire to stay in control at all times, would never allow herself to let go and truly _be_ with him. _Don't make her settle for you_, Brian's malevolent subconscious warned.

"I don't want to hurt you. You deserve much more in life than me."

Olivia's eyes widened as stared at him, forcing her eyes to refocus. Brian wiped a sleeve across his eyes and bent to pick up his luggage. He looked heartbroken and she had to think fast before he disappeared. She had told him she loved him; he didn't believe her? They had their fair share of arguments and excelled at lobbing snarky comments at each other. But they always made up, with pride-swallowing apologies and night-long sex. She had given up trying to conceal their relationship after being discovered by accident, wearing only Brian's shirt at the time. She even tolerated her colleagues teasing her about Brian, and secretly loved the attention. She had depended upon Brian after being held by William Lewis; he was her support, her comfort. Never in her life had she ever needed somebody like she did then. _And now, I still need him now_, she thought.

"It's okay, Liv," he put his hand on the door. "I don't think we want the same things."

"Like what?" she whispered.

Brian bit his lower lip, casting his eyes down. "Don't worry about it."

"What don't we want, Bri?"she tried again, her fingers barely touching his arm before he pulled away.

"Forever," his voice was so quiet, she almost missed it. He cleared his throat. "I'll get the rest of my stuff later. Let you have your space. It's what you like."

_Forever_, she thought. _He wants forever?_ Suddenly, a spike of anger shot through her.

"Hold on," she said loudly, breaking the unsettling quiet of the apartment. "You're telling _me_ that I don't want forever? Who are you to presume anything?"

His eyes narrowed and he crossed his arms, defenses raised. A fire had been lit within Olivia's eyes and he stayed silent, watching her solve the puzzle he had left her with. Her cheeks were flushed as she stood, hands on hips, glowering at him.

"What the hell is wrong with you, Brian Cassidy?!" she yelled. "You tell me that I never talk about anything, but here you are, guilty of doing the same thing. Spit it out, Cassidy. What is it you don't think _I_ want?"

He stepped into her space. "Us, Olivia. I don't think you honestly want us," he spat. "Not the way that I do."

They were breathing heavy, hurt and anger pulsating in each of them. Olivia's jaw clenched and she crossed her arms, mirroring Brian's stance.

"Prove it."

Brian raised an eyebrow, weary of her challenge. They stared at each other, tension filling the room, each of them suffocating under its intensity. She didn't flinch until he angrily threw the duffel bag on the floor and ripped it open. Her readiness to pick a fight vanished when he thrust a velvet box into her hands.

"Happy?"

Brian stormed past her into the living room. He sank onto the couch, one hand massaging his aching forehead. He didn't dare look at her. He heard her breathing move closer to him, and forced his eyes to stay planted on his feet. It was frightfully quiet in the apartment; the only sounds were their unsteady respirations.

"You are walking out on me because you want to marry me?" she questioned, gripping the jewellery box as if it were a lifeline.

Brian looked up at her. His heart clenched, seeing tears streaming down her beautiful face. Her eyes showing him her confusion and surprise. If it were any other argument, he would have leapt up and gathered her in his arms, whispering his love into her ear and kissing her hair. He wiped a tear from his face, and leaned on his knees, eyes on the blank television screen across from the couch.

"Ask me," she whispered.

His heart sped up. _She shouldn't have to settle for you!_ his inner-voice sneered. He looked at her face again, watching her full lips quiver as she silently cried. She slowly held out the box, it's unspoken promise begging to be heard. His hand shook as he took it from her and turned to face her, sitting on the edge of the couch cushion. He took a deep breath, trying to quash the monotonous self-deprecating dialogue in his mind.

"Olivia," he risked eye contact with her, and his heart melted. "Olivia, will you marry me?"

The box popped open and a stunning triple-diamond ring shone, piercing the darkness that shrouded the couple. Olivia licked her lips, staring first at the engagement ring and then looking deep into Brian's eyes. She knelt in front of him.

"Yes."

Brian caught himself before happiness overwhelmed his senses. "Are – are you sure, Liv?"

To his surprise, Olivia laughed, tears still falling. "Cassidy, give me the damn ring."

He couldn't help himself; he chuckled. A weight lifted off his heart, and Brian gently took her hand. He slid the ring on her finger and kissed her knuckles.

"I'm sorry," he murmured, squeezing his eyes shut as another tear slid down his cheek. He felt her other hand lift to caress his face.

"Look at me, Bri," Olivia gently whispered. He raised his head and gazed at her, taken aback by the loving glow on her face. She had never looked so happy, so radiant. Her eyes still glistened with tears, but her smile was enough to brighten any night. "I love you, and I want to spend the rest of my life with you, as your wife. For better or for worse."

His heart soared, his elation stomping out the uncertainty that had been burning within his soul for so long. He pulled her up onto his lap and kissed her with an explosion of love that made Olivia happily breathless. Her mouth moved against his and she held onto him for dear life.

"I love you, Liv. I- I'm sorry I doubted-" he was stopped by her fingers on his lips.

"I'm sorry I sent mixed signals all the time," she said, tenderly stroking his face. "I do want us forever, Bri. Please believe me, I do."

He took her face in both hands and softly pressed his lips to hers. The kiss was feather-light, and they pulled apart looking deep into one another's eyes. Both smiled and leant forward again, this time with lust spurring their movements. Brian pulled Olivia tighter to his body, feeling himself hardening under the heat of her body. She moaned and began grinding against him. His hands pushed her sweater off, quickly unhooking her bra. Once her full breasts were exposed, he took one in his mouth, sucking and pulling at her nipple. Olivia cursed aloud, his action sending a fiery spark of arousal between her thighs. She pushed his jacket off his shoulders as he continued to suck and paw at her breasts. His mouth detached as she reached down to tug his shirt off, tossing it onto the floor.

"Olivia," he breathed, his breath making goosebumps prickle her flesh. His eyes were full of love and desperation to take her. His hands stroked up and down her shoulders and back. She ran a hand over his hard cock, still restrained by his jeans. He groaned and she stood up, quickly undoing her pants. His eyes followed as her skin was uncovered. She smiled and bent over him, grabbing his belt. He let her pull his pant and boxers in one tug, freeing his manhood. She bit her lower lip and pushed her damp panties down her legs. Brian's fingers traced her wet slit and she shuddered.

"Not yet," she said, kneeling before him. She kept her eyes on his as she softly ran her tongue around the head of his cock. Brian groaned, one hand coming up to grab her hair. She grinned and slowly licked down to his balls, sucking them into her hot mouth one at a time. Her tongue traced its way back up his shaft before engulfing his thick cock in her mouth. Brian seethed, feeling his dick hit the back of her throat.

"Fuck…"

Olivia sucked on his head and swirled her tongue around the tip. His cock was thick and always felt incredible in her mouth. She closed her eyes and hummed against his flesh as she bobbed her head. He was big, but she did her best to deep-throat, one hand coming to rub his balls. His moans kept her at an eager pace. She massaged with one hand as she let him push his cock further down her throat.

"Fuck, baby," he groaned, holding her hair back to watch her. "God, Liv."

She sped up, feeling him start to tense. He pulled back on her hair, gently telling her she could stop. Instead, she shook her head, mouth full of his cock. She let him go with a pop and sensually kissed his head.

"Let me taste you, baby."

Brian groaned loudly, pushing her mouth back onto his cock. He had never experienced anything as incredible as having Olivia downing his dick, wanting to suck the come right out of him. His whole shaft tingled and his heart raced. She took him deep in her throat and he could no longer hold back. His seed hit the back of her throat as Olivia kept fucking him with her mouth. She swallowed his come, licking any remnants off of his cock.

"God, baby, you have no idea how hot that was," she smiled up at him. He growled, lifting her to her feet and laying her down on the sofa.

"I think I have some idea," he replied, licking her lips as he pushed two fingers into her wet center. "So fucking wet."

Olivia cried out as his fingers curled inside of her. She kissed his neck and bit his shoulder. The sensation of him fingering her sent her into another realm of pleasure. He whispered against her ear, telling her how unbelievably sexy she was. She felt her pussy begin to clench his fingers and she clawed his back.

"Baby, fuck me!"

Brian removed his fingers, quickly licking them clean as she moaned watching him. She pulled his mouth to hers, tasting her juices on his lips. His breath held her scent and she felt herself get even more turned on. They kissed, tongues battling. He pushed his cock inside of her, bringing one hand down to rub her clit.

"Harder!"

Brian grunted as he pulled out of her and roughly pushed back in, filling her completely. Olivia cried out his name, meeting his hips with each thrust. The pleasure cascaded through her body as they moved as one. She felt her muscles begin to tighten around his cock. A scream ripped through the apartment as she came. Brian kept his pace, still teasing her hypersensitive clit as his cock started to tense inside of her.

"Bri – Bri –" she struggled to speak as a second orgasm flooded her body. Feeling her let go a second time, Brian yelled her name as he came deep inside of her. He leaned his forehead on her shoulder as her pussy finished convulsing around his cock.

"Mmm, you should pack your bags more often, baby," her breath tickled his ear as she teasingly chuckled.

Brian ran his hand up one side of her body, and raised himself up to gaze upon her. He brushed her hair out of her face, his thumb softly tracing the shape of her cheek. She smiled at him, her eyes happy and full of adoration. He kissed her lips, letting her bite his lower lip before he pulled back again.

"Uh-uh," he grinned. "Wherever I go, I'm taking you with me."

Olivia's heart swelled, and she wrapped her arms around his neck. Her fingers found the new piece of jewellery and she couldn't help lifting her left hand to stare at the sparkling stones. She returned her eyes to his.

"I love you, future husband," she told him sweetly.

"I love you, future wife."


End file.
